The world is now firmly on course for the worst-case scenario in terms of climate change, with average global temperatures rising by up to 6C by the end of the century, leading scientists have warned. Such a rise � which would be much higher nearer the poles � would have cataclysmic and irreversible consequences for the Earth, making large parts of the planet uninhabitable and threatening the basis of human civilisation. We are headed for it, the scientists said, because the carbon dioxide emissions from industry, transport and deforestation which are responsible for warming the atmosphere have increased dramatically since 2002, in a way which no one anticipated, and are now running at treble the annual rate of the 1990s. This means that the most extreme scenario envisaged in the last report from the UN Intergovernmental Panel on Climate Change, published in 2007, is now the one for which society is set, according to the 31 researchers from seven countries involved in the Global Carbon Project. Although the 6C rise and its potential disastrous effects have been speculated upon before, this is the first time that scientists have said that society is now on a path to meet it. The Global Carbon Project study, led by Professor Corinne Le Qu�r�, of the University of East Anglia and the British Antarctic Survey, found that there has been a 29% increase in global carbon dioxide emissions from fossil fuel between 2000 and 2008, the last year for which figures are available. On average, the researchers found, there was an annual increase in emissions of just over three per cent during the period, compared with an annual increase of one per cent between 1990 and 2000. Almost all of the increase this decade occurred after 2000 and resulted from the boom in the Chinese economy. The researchers predict a small decrease this year due to the recession, but further increases from 2010. In total, carbon dioxide emissions from the burning of fossil fuels have increased by 41 per cent between 1990 and 2008, yet global emissions in 1990 are the reference level set by the Kyoto Protocol, which countries are trying to fall below in terms of their own emissions. The study by Professor Le Qu�r� and her team, published in the journal Nature Geoscience, envisages a far higher figure. "We're at the top end of the IPCC scenario," she said.